Double switch



FIG. 1 is a perspective view of a double switch, showing my new design;

FIG. 2 is a side elevational view thereof, the side opposite that shown in FIG. 2 being the mirror image thereof;

FIG. 3 is a top plan view thereof; and,

FIG. 4 is a front elevational view thereof. 

The ornamental design for a double switch, as shown and described. 